Man...tough, tough, tough. My old Md 29 8 3/8" 44 Mag I really love. Several Sigs, the little Colt Mustang, the Ruger .22 Mark III. If I HAD to narrow it down to just one fave, I think it would have to be my old West German SIG P220.
Absolute buttery trigger, I really like the decocker DA/SA, very accurate, fits the hand like a glove. Way back in the early 90's, my buddy went for the flash and bought a .44 Desert Eagle. I went for the SIG P220 .45ACP. My poor-ass self at the time really had to scrimp and save for quite awhile to get it, but it will always be with me.